Custom login form redirect on error

Hello there,

I have made a custom login and put it into my template. It works perfectly well. I have also created a password recovery form that also works. My aim is to not have the end user get to the wordpress admin backend. However they can by typing an incorrect username and password into the login form i’ve made, which will then redirect you to the wordpress admin backend saying that the username and password has not been found etc. Is there a way around this? Its quite an urgent matter as the site needs to be live very soon.

Any help would be greatly appreciated
Cheers
Dan